Mining drill bit extractor



Feb. 10, 1953 c. J. KING MINING DRILL BIT EXTRACTOR Filed D60. 31, 1947 Inventor CLIFFORD J KING Attorney.

Patented Feb. 10, 1953 UNITED STATES PATENT OFFICE.

MINING DRILL BIT EXTRACTOR GlifiordJrKing, Malartic', Quehec anada,

Anulicationnecemhersl, 194.7; Serial, 1 Io.- 794,970

11 Claims. 1

The invention relates to; improvements in a mining drill bit extractor and'appertains-particularly to av portable, pneumatically'operated unit that, is compact and easy to carry, can-bequickly connected to the usual air-hose-line in themine and facilitates the sure and speedy removal of a dulled or damaged bit right on the job, where space it limited, and Working condit ons: poor; without.- loss of time or riskof damaging; the shank.

It is an object of the instant inventionlto provide apneumatic, portable unit; where the'valve lever serves also as a carrying handle;- that is designed to clean the bore in the bit and shank; separate them and then throw both clear ofthe machine, dropping the former vertically and'horizontally ejecting the latter.

A further object of the invention is to provide an extractor of the nature, and'character described that is characterized by structuralsim-v plicity; durability and efli'ciency and being capable. of manufacture at reasonable costis thereby rendered commercially desirable.

To the accomplishment of these and'related'objectsas. shall become, apparent as the description proceeds, the invent on resides-in the construction, combination and arrangement of parts as shall be hereinafter more fully described, illustrated in the accompanying drawings, and pointed out in the claims hereunto appended.

The invention will be best understood and can be more, clearly described when reference is had to the drawings forming a part of this disclosure wherein like characters indicate like parts throughout the severaL views,

In the drawings:

Figure 1 is a longitudinal, vertical section through the extractor, with a bit and shank therein shown in, elevation and in position to be separated;

Figure 2 is, anrelevation or the shank ejecting end thereof;

Figure 3 is a plan view of'the piston; and

Figure 4 is an elevation of the inside of the shank-passing anvil, against which the piston and bit are driven.

In hard rock mining, it is usual practice to afiix the drill bit tightly on the drillsteel' shank. During the process of drilling these bits are dulled and damaged and need to be replaced yet often become secured so fast that their removal is quite difficult.

The separation of bit and shank is usually done by simply hammering the bit until it. loosens but this'is a lengthy, tedious task and not infrequently 2. results in damage to the shank. Usually-"per: formed underground, it is the more difiiculteof space'limitations and poor-working conditions:

The present pneumatic extractor; using: the conveniently available air-hose, is a simple com pact and easy-to-carry device that quickly and positively eiiects the required removal of the dulled or damaged bit from theshank; simultaneously clearing'the bore of the latter, so thatit'xi-s readied for, further"service instantly and undamaged;

The portable extractor comprises essentially a frame work or-body having a horizontally extending cylinder" 5 supported'at oppositeends by vertical end members or blocks 6 with confrontin annular troughs: I in which the ends of the cylinder 5 are set. A concentric guard sleeve 8; shorter than the cylinder by the-combined depth of the slots 1, surrounds the cylinder 5 to protect it against iniury from external blows and. is supported in spaced relation therefrom by four external, longitudinally extending circumferentially spaced bolts 9 that pass also through the end blocks '1 and are secured bynuts In to maintain the whole-assembly.

As distinotfrom the body of the extractor that may be of mild steel, a hardened steel disk H, of the same diameter as and concentric with the cylinder 5 is seated. in a recess 12 in the'inside of the front or delivering end block;6 and' positioned there as bya dowel pin I3. Actuallythe cylinder-accommodating trough I, in this end, i y l nor sho ldenonth perimet ofthis; disk I-l.

The far or inner end block 6 housesaspr-lng closed valve 1.4, m-anually opened by a lever; 15 hinged at its remote end and extending more than half way to the front end of the extractor, paralleling and spaced above the guard sleeve 8; where it is afiorded limited'vertical movement in a longitudinally slotted, transversely disposed uide bracket l6 welded on the-said sleeve. The lever'arm thus serves as a convenient handle for carrying the device about, A compressed air line hose ll' connects below the valve M while above the valve a large inlet port I8 communicates with the interior of the cylinder '5. Slidable withinthe cylinder 5 is a piston [9 provided with a skirt portion Zil. The piston head has a concave pocket or recess- 2! onits outer surfaceand ineludes also a small axial bore or vent 22.

To admit and facilitate theinsertionofa drill steel shank and bit, the guard sleeve 8 and" cylinder' 5 are both cut away at the top'near the forward end to provide an opening 23 adequate to pass the drill bit 24 shown in Figure 1. Similarly the top of the free end of the piston skirt 2B is removed as at 25. In continuance of the opening 23, the near end block 6 and anvil disk i l are vertically slotted as at 26 to a point below the centre to receive the drill shank 21 dropped horizontally therein and that is free to slide longitudinally therethrough. Likewise the bottom of the free end of the piston skirt 20 has a corresponding opening 28 and the forward end of the guard sleeve -8 and cylinder are both cut away at the bottom, directly below the entrance opening 23, to provide an outlet opening 29 through which a freed bit drops out to clear the extractor, leaving it ready for further use.

In use the drill steel shank with the tightly secured bit that is to be extracted-is dropped into the extractor through the opening 23 and slot 26, the bit centered in the piston, the skirt of which is longer than the drill bit and the loaded piston is then pushed in to the back or valved end of the cylinder, the vent 22 in the piston head serving to relieve the pressure. The extractor is n-ow ready, and by pressing down on the hand lever 15, air entering through the valve IA strikes the piston head literally throwing the bit 24 against the disk or anvil I I While the shank 27 is driven outwards through the slot 25, being freed from the tight bit on the impact of the bit with the arresting anvil. The bit drops through the cut out 28 in the piston and outlet opening 29in the cylinder and sleeve leaving the extractor ready for subsequent use. Some of the impelling blast of compressed air finds egress through the piston head vent and passes also through the axially bored bit and hollow steel shank, cleaning them of any rock dust, dirt or other obstruction.

' From the foregoing description taken in connection with the accompanying drawings, it will be manifest that a mining drill bit extractor is provided that will fulfil all the necessary requirements of such a device, but as many changes could be made in the above description and many apparently widely different embodiments of the invention may be constructed within the scope of the appended claims, without departing from the spirit or scope thereof, it is intended that all matters contained in the said accompanying specification and drawings shall be interpreted as illustrative and not in a limitative or restrictive sense.

"Having thus described the invention, what I claim as new and desire to secure by Letters Patent is:

l. For a pneumatic bit extractor, a cylindrical body, a'p'air of end blocks recessed on confronting sides to seat the ends of said cylindrical body, a concentric guard sleeve surrounding said cylindrical body, a plurality of 'circumferentially spaced bolts with cooperating nuts extending longitudinally of said extractor, exterior of said guard sleeve and uniting said end blocks, an opening through the stop of said cylindrical body and guard sleeve at one end, a vertical slot continuing down therefrom in the adjacent end block to a point below centre, an outlet opening through the bottom of said cylindrical body and guard sleeve in substantial vertical registry with said first mentioned opening for the evacuation of a freed bit, a valved inlet port in the opposite end block and a piston slidable in said cylindrical body having an axial perforation through the head thereof and a skirted portion of greater length than the mining drill bit, the

'4 open end of said skirted portion having a cut out at both top and bottom, corresponding with the said openings in said cylindrical body and guard sleeve respectively.

2. A device for separating partially telescoped members in tight frictional relationship which comprises a tube, a slotted abutment block at one end of the tube, an inlet mouth in said tube aligned with the slot in said block, a piston slidable in the tube having an inlet mouth in the side wall thereof adapted to be aligned with the inlet mouth of the tube for receiving the telescoped members therein, and means for introducing fluid under pressure into said tube against said piston for impacting one of the telescoped members carried by the piston against the abutment block while allowing the other member to pass freely through the slot thereof.

3. A device as described in claim 2 wherein the slot in said block is narrower than the inlet mouth in said tube and extends more than half way down the block,

4. The combination with the structure set forth in claim 2 and wherein said block has a circular recess in its inner face, of an anvillike disk seated in said recess, said disk having a slot similar to and in registry with the slot in said block.

5. The combination with the structure set forth in claim 2 and wherein said block has a circular recess in its inner face, of an anvillike disk seated in said recess, said disk having a slot similar to and in registry with the slot in said block and disk-positioning means disposed in aligned bores in said disk and block to assure registry of their respective slots.

6. The combination with the structure set forth in claim 2 of an axial bore through said piston whereby some of the fluid under pressure in said tube is directed against the partially telescoped members being acted on.

7. A device for separating partially telescoped members in tight frictional relationship which comprises a tube, a block at one end of said tube and a slotted abutment block at the other end of said tube, an inlet mouth in the top of said tube aligned with the slot in said slotted abutment block, said blocks each having in their confronting faces an annular trough in which the ends of said tube are seated, a guard sleeve loosely surrounding said tube in circumferentially spaced relation thereto and having an inlet mouth in registry with the mouth in said tube, a plurality of longitudinally extending circumferentially spaced bolts with cooperating nuts positioned exteriorly of said sleeve and uniting said blocks, a piston slidable in the tube having an inlet mouth in the side wall thereof adapted to be aligned with the registering inlet mouths of the tube and sleeve for receiving the telescoped members therein, and means for introducing fluid under pressure into said tube against said piston for impacting one of the telescoped members carried by the piston against the abutment block while the other member is allowed to pass freely through the slot thereof.

8. The combination with the structure set forth in claim 7 of a valve lever for said fluid-introducing means, said lever being hinged on the non-slotted end block with its free end extending more than half way to the far end of the device and a guide bracket for said lever mounted on said guard with a slot through which the free end of said lever extends, said lever serving also as a carrying handle for the device. REFERENCES CITED P combmation with the structure set The following references are of record in the forth in claim '7, of aligned openings through me of this patent: the bottom of said tube and said guard near said slotted abutment block. 5 UNITED STATES PATENTS 10. The combination with the structure set Number Name Date forth in claim 2, of means for limiting the ap- 37,195 Fitzgerald Dec. 16, 1862 proach of the piston to the slotted abutment 513,362 Foster et al. Jan. 23, 1894 block to a greater distance than the axial length 618,324 Blum Jan. 24, 1899 of the telescoped member impacted against the 10 632,838 Jacobs Sept. 12, 1899 said slotted abutment block. 702,979 Martin June 24, 1902 11. The combination with the structure set 1,393,094 Ditson Oct. 11, 1921 forth in claim 2 of a skirt on said piston pro-f 2,343,445 Craig Mar. 7, 1944 jecting toward said slotted abutment block 0 a greater length than the axial length of the 15 FOREIGN PATENTS telescoped member impacted against the said Number C01mtry D 1mm t t block, 533,390 Great Britain Feb. 12, 1941 CLIFFORD J. KING. 

